<template>
  <div>
    <el-upload
      action="http://oa-314-2.oss-cn-guangzhou.aliyuncs.com"
      :data="dataObj"
      list-type="picture-card"
      :file-list="fileList"
      :before-upload="beforeUpload"
      :on-remove="handleRemove"
      :on-success="handleUploadSuccess"
      :on-preview="handlePreview"
      :limit="maxCount"
      :on-exceed="handleExceed"
    >
      <i class="el-icon-plus"/>
    </el-upload>
    <el-dialog :visible.sync="dialogVisible">
      <img width="100%" :src="dialogImageUrl" alt>
    </el-dialog>
  </div>
</template>
<script>
  import {policy} from './policy'
  import {getUUID} from '@/utils'

  export default {
    name: 'MultiUpload',
    props: {
      // 图片属性数组
      value: Array,
      // 最大上传图片数量
      maxCount: {
        type: Number,
        default: 30
      }
    },
    data() {
      return {
        dataObj: {
          policy: '',
          signature: '',
          key: '',
          ossaccessKeyId: '',
          dir: '',
          host: '',
          uuid: ''
        },
        dialogVisible: false,
        dialogImageUrl: null
      }
    },
    computed: {
      fileList() {
        const fileList = []
        for (let i = 0; i < this.value.length; i++) {
          fileList.push({url: this.value[i]})
        }

        return fileList
      }
    },
    mounted() {
    },
    methods: {
      emitInput(fileList) {
        const value = []
        for (let i = 0; i < fileList.length; i++) {
          value.push(fileList[i].url)
        }
        this.$emit('input', value)
      },
      handleRemove(file, fileList) {
        this.emitInput(fileList)
      },
      handlePreview(file) {
        this.dialogVisible = true
        this.dialogImageUrl = file.url
      },
      beforeUpload(file) {
        const _self = this
        return new Promise((resolve, reject) => {
          policy()
            .then(response => {
              console.log('这是什么${filename}')
              _self.dataObj.policy = response.data.policy
              _self.dataObj.signature = response.data.signature
              _self.dataObj.ossaccessKeyId = response.data.accessid
              _self.dataObj.key = response.data.dir + '/' + getUUID() + '_${filename}'
              _self.dataObj.dir = response.data.dir
              _self.dataObj.host = response.data.host
              resolve(true)
            })
            .catch(err => {
              console.log('出错了...', err)
              reject(false)
            })
        })
      },
      handleUploadSuccess(res, file) {
        this.fileList.push({
          name: file.name,
          // url: this.dataObj.host + "/" + this.dataObj.dir + "/" + file.name； 替换${filename}为真正的文件名
          url: this.dataObj.host + '/' + this.dataObj.key.replace('${filename}', file.name)
        })
        this.emitInput(this.fileList)
      },
      handleExceed(files, fileList) {
        this.$message({
          message: '最多只能上传' + this.maxCount + '张图片',
          type: 'warning',
          duration: 1000
        })
      }
    }
  }
</script>
<style>
</style>

